This invention relates to controlling sheets such as banknotes which carry magnetic printing, and relates especially to recognizing, validating, stacking, picking and otherwise handling such notes.
At the time of writing, magnetic printing is used on banknotes in US dollars. It is known that the magnetic signatures of such notes can be used for validation and/or recognition, but the signature weakens with age, making validation and recognition more difficult.
With any banknote, precise physical control is important for dispensing by use of an automated teller machine (ATM); when notes are picked from a stack, double picking must be avoided.